-- latest in the horrifying Powell family tragedy police haven't covered a new grisly clue that could prove Josh Powell killed his wife Susan. This as a memorial service is set to be held today for their two young sons. ABC's Abbie Boudreau has the story from Seattle good morning -- Good morning -- a shocking new discovery overnight police are hoping to finally figure out what happened to Susan Powell. Hoping to solve this two year long mystery. A possible break in the case police revealing they discovered a bloodstain comforter in Josh -- Washington storage unit. Investigators said Friday Powell visited the unit the day before he killed himself. And his two young sons. Initial tests of the -- turned up positive for blood but it remains a mystery -- that blood is his missing wife Susan. And we're now learning more about the moments leading up to the explosion. Police released this surveillance image of Josh Powell from the day before the murders showing him withdrawing 7000 dollars from a local bank. He may have also been spotted at a landfill. Detectives say they received a tip he -- something in the recycling. May -- find anything we haven't yet but we're covering -- basis. And a new twist to the investigation. Police now closing in on Josh Powell's father Steve -- calling him a person of interest in Susan's disappearance. Stephen is sitting in jail right now on unrelated charges of child pornography. He claimed in an interview with me last year he shared a sexual relationship with his daughter in law though police say that's untrue. We interacted and -- a lot of sexual ways do you think a part of you started falling in opera season. Yeah Conceicao. And -- -- end and there's no question in my mind that the feelings were mutual. Despite the hostility and anger between students parents and the Powell's. Later today both families will lay to rest two innocent boys. Charlie and -- Who endured more than a two year long public nightmare since their mother -- disappear. More than a thousand people are expected to attend today's funeral. Such a large crowd they actually had a change of venues to accommodate everybody. And -- I can tell you it is a very very sad day out here this is the kind of loss that affects the entire community.

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